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LEE BOW EFFECT |
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Isis
Really should get out more Joined: 01 Sep 05 Online Status: Offline Posts: 2753 |
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Topic: LEE BOW EFFECT Posted: 20 Oct 11 at 10:44am |
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Why didnt you say so before? Let me know exactly what youd like set up and il run it in the tank if I have some free time next week. In the mean time we look forward to the rest of these vector diagrams. |
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G.R.F.
Really should get out more Joined: 10 Aug 08 Location: United Kingdom Online Status: Offline Posts: 4028 |
Post Options Quote Reply Posted: 20 Oct 11 at 10:58am | ||
Do this..
Get a little model row boat (preferably with a curved hull if you can't find anything with a foil) Get your flow going evenly. Tie one end secure = boat lines up with current, nothing proved Secure boat at 45 degrees to current watch what happens.
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Oatsandbeans
Far too distracted from work Joined: 19 Sep 05 Location: United Kingdom Online Status: Offline Posts: 382 |
Post Options Quote Reply Posted: 20 Oct 11 at 11:16am | ||
This is the problem with your theory, it relies on the boat being secured to a stationary point. If that is done yes the foil will generate lift from the tidal flow over it, but the boat is not held stationary, the boat is free and will move around as the water moves around. There will be no flow over the foils apart from the flow that is derived from the normal movement of the boat, and the boat will not be aware of the effects of the tidal flow.
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Isis
Really should get out more Joined: 01 Sep 05 Online Status: Offline Posts: 2753 |
Post Options Quote Reply Posted: 20 Oct 11 at 11:39am | ||
Exactly. Or think of it this way - Imagine you are sitting in your V-twin on a totaly calm day, anchored in the middle of a channel with a 2 knot drift. Move the rudder to one side and let me know what happens. Now cast off your anchor and drift with the current. Move the rudder again. In one of these scenarios there is flow over your foils due to the current. In the other scenario you are not anchored. For what its worth the likes of Stan Honey, Lowell North and Peter Isler are all sitting on Dave Perrys side of the fence. |
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rogue
Really should get out more Joined: 04 Dec 08 Location: United Kingdom Online Status: Offline Posts: 978 |
Post Options Quote Reply Posted: 20 Oct 11 at 12:34pm | ||
not me chap... this guy clearly knows more than you or I... |
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2547
Really should get out more Joined: 11 Aug 11 Online Status: Offline Posts: 1151 |
Post Options Quote Reply Posted: 20 Oct 11 at 12:39pm | ||
I think we are getting to the bottom of GRPs confusion ... his perpetual motion theories all seem to rely on his reference point being the ground (as if anchored) rather than moving on the current as per the moving carpet or table cloth models ... |
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pondmonkey
Really should get out more Joined: 12 Aug 11 Online Status: Offline Posts: 2202 |
Post Options Quote Reply Posted: 20 Oct 11 at 12:40pm | ||
no he wouldn't. All a pondmonkey does know is that like any other flow controlled by the moon, it's best avoided, even in a wetsuit.
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2547
Really should get out more Joined: 11 Aug 11 Online Status: Offline Posts: 1151 |
Post Options Quote Reply Posted: 20 Oct 11 at 12:49pm | ||
Ah ... but do pondmonkies notice strange happenings when someone pulls the plug out of the dam? |
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pondmonkey
Really should get out more Joined: 12 Aug 11 Online Status: Offline Posts: 2202 |
Post Options Quote Reply Posted: 20 Oct 11 at 12:57pm | ||
only that the baby goes out with the bathwater
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rb_stretch
Really should get out more Joined: 23 Aug 10 Online Status: Offline Posts: 742 |
Post Options Quote Reply Posted: 20 Oct 11 at 1:03pm | ||
I think GRF is just breaking the different components down to illustrate a point. The motion of the boat due to the wind is what provides the interaction with the tidal force.
And I think everyone does agree that the tide has an impact performance depending on where it is coming from.... |
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